YouTube’s popularity has prompted some to make business out of it making them celebrities of sorts.

YouTube has become the go-to destination for people to share their videos. Some have made a business from it and become celebrities of sorts in the process.

Their channels showcase videos on treating common ailments, the latest gadget reviews, recipes and how they make money through advertisements.

Here’s a look at some of the most popular in India.

Vikram Yadav: A doctor by profession, Mr. Yadav started his YouTube channel in 2009 after drawing inspiration from University of South Carolina video lectures about microbiology and immunology.

He was pursuing his undergraduate degree in medicine at that time. “I liked those lectures a lot. I thought I should also do something similar, “said Mr. Yadav.

His channel has more than 89,000 subscribers.

Mr. Yadav, 31, uses his videos to explain various diseases and how to treat them. His patients feature in some episodes. The clips can be quite graphic, for example, in this video he explains how to treat a cyst on the neck.

He produces two videos every week on average. The doctor says he is guided by the severity of his patients’ symptoms when it comes to choosing what ailment he should feature.

A native of Moradabad district in Uttar Pradesh, northern India, Mr. Yadav says the response to his videos has been favorable. He regularly receives emails from his subscribers congratulating him on his work.

He plans to make videos on biochemistry, pathology, anatomy and others. “It will take a lot of hard work but I will do it,” said Mr. Yadav.

Nisha Madhulika: This 54-year-old housewife in Noida, a suburb of Delhi, became an avid user of the Internet after her passion for cooking led her to launch nishamadhulika.com in 2007 to share some of her recipes.

“I didn’t expect people would praise my work right from the first day,” said Ms. Madhulika.

Her readers repeatedly demanded video tutorials, so she launched her YouTube channel in mid-2011.

Her eponymous channel is a cooking guide featuring her own recipes as well as those suggested by her audience of 60,692 subscribers. Recipes range from a simple dal or a peanut chocolate bar snack to exotic dishes such as watermelon rind curry and a mango cake.

Her husband, M.S. Gupta, who runs a software and website development company, would shoot the video, edit and upload it. Within four months, Ms. Madhulika had produced 200 videos. One of her first demonstrated how to make Gulab Jal (rose water.)

In October 2011, Ms. Madhulika hired a professional cameraman and a video editor to shoot, edit and produce videos for her channel.

Today, she produces around 20 videos a month and spends around six hours a day working on her recipes and shooting videos. “There is no holiday for me,” she said.

“I always think of ways to make a particular recipe in an easier manner, “she said. “I make sure the ingredients I use are not only easily available but also make the recipe taste good and healthy,” she added.

Sometimes, her readers ask her to make recipes that she has never heard of, such as Sakoda, a dish made from spinach. She scours the web, reads books, asks her friends and relatives for information about the recipe. “It is always at the back of mind as to how can I fulfill the demands of my audience,” said Ms. Madhulika, who is originally from Agra. She holds a bachelor’s degree in science and did a short course on business management in Bhopal, in central India’s Madhya Pradesh state.

She initially started out assisting her husband with his software business. But she always wanted to work independently.

“I never thought I would have work of my own that will give me so much happiness,” she said. “This is more than just a job to me,” she added.

Ashwin Ganesh: Acollege dropout, Mr. Ganesh started his channel in late 2011. Within three months he had 800 subscribers.

Mr. Ganesh’s relationship with YouTube started when he bought Samsung’s Galaxy Note. He tried to explain the technical features of the device to his friends but they weren’t particularly interested. “All they wanted to know was whether it could run [the game] Angry Birds,” he said.

Undeterred, he decided that he might get a better response on the Internet and made a video explaining the features of his phone.

At the latest count, Mr. Ganesh had 52,426 subscribers.

He produces 25 videos a month on average but doesn’t have fixed work hours. “One of the biggest advantages of being your own boss, I guess,” said Mr. Ganesh.

His channel mainly focuses on reviews of smartphones and tech tutorials about things such as “rooting” Android phones. Rooting is a technical process that gives access to cellphone functions that are otherwise restricted for regular users.

Mr. Ganesh started making videos with a basic digital camera and was initially skeptical about whether his channel would be a success. As his channel grew in popularity, he upgraded his equipment. Now he has a professional camera and a microphone with a noise cancellation feature.

But the real reason behind attracting a large number of viewers to his channel lies in his ability to break down complex technical processes for the layman, said the 25-year-old who lives in the southern city of Chennai.

In the future, Mr. Ganesh plans to finish his studies and redesign his website. But this doesn’t mean YouTube will take a backseat. “I plan to do this fulltime,” he said.

Ranjit Kumar: Ranjit Kumar, 36, makes gadget-related videos ranging from taking mobile devices out of their box and setting up a wifi network in a home, to reviews and tech tips.

A freelance IT consultant by profession, with experience in a website development company, Mr. Kumar would often be sought by friends and relatives for advice before buying a gadgets like mobile phones, laptops or gaming consoles. He decided to start making videos to give this guidance to a wider audience and launched his YouTube channel, Geekyranjit, in 2011.

“You don’t have to read six to seven pages to understand a product,” said Mr. Kumar. “Watch a video for five-seven minutes, that gives you better understanding.”

Success wasn’t easy for Mr. Kumar.

“For the first year, the views were very low,” he said. “I was actually disappointed,” he added.

But he persevered.

Mr. Kumar began focusing on video reviews of mobiles and tablets because, he says, they were the biggest traffic drivers to his channel.

“I am trying to stick to tier-one brands like Samsung, Nokia, HTC and Sony,” he said, adding that covering every brand is not possible as there are too many mobile companies.

Mr. Kumar spends six to eight hours every day making videos for his YouTube channel, and produces eight to ten videos in a week.

Mr. Kumar makes it a point to answer the queries of his subscribers and he tries to review the gadgets requested by them as often as possible.

“I engage with the audience,” he said. “Maybe that is the reason why people like my channel.”

The site can be all consuming though, Mr. Kumar says.“Lately, even I have noticed that I am spending too much time on YouTube,” he said.

His channel has nearly 43,000 subscribers.

Mr. Kumar, who lives in Hyderabad in southern India, used to spend 12 hours a day teaching himself how to write software codes during his college days. He completed his bachelor’s in commerce, and studied programming at the Centre for Development of Advance Computing in Maharashtra, a government research and development body that also offers IT training programs. “To be very frank, I didn’t learn anything in CDAC because I knew everything,” he said.

Besides playing with gadgets and writing software codes, Mr. Kumar likes listening to rock and pop music and runs a gadget review website Tech2Buzz.com. But working on his YouTube videos leaves him with little time.

“I enjoy what I am doing,” he said. “The day I stop enjoying it, I will stop it.”

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